Disclosed herein is a seat frame, and specifically a seat frame having a structure in which a side frame is fixed to each of both end portions in the width direction of a pan frame.
A seat frame in which a side frame is fixed to each of the both end portions in the width direction of a pan frame has already been known as a seat frame structure, and such a structure is utilized for a frame of a vehicle seat, specifically, a frame for a seat cushion (hereinafter, referred to as a seat cushion frame). As an example thereof, in Japanese Patent Document No. 2012-214119 A (“the '119 Document”), disclosed is a seat cushion frame having a structure in which a pan frame is installed at the front end portion of a pair of side frames separated from each other in the right and left direction.
In order to appropriately mount the side frames to a pan frame, rigidity appearing on the side frame side, or more precisely, rigidity for mounting the side frame to the pan frame has to be secured.
Further, a connecting member by which a pair of side frames are connected with each other is provided in the seat cushion frame which has been disclosed in the '119 Document, but in cases where this connecting member and the side frame are joined to each other via welding, it is preferable that welding is performed at the portion where rigidity of the side frame can be expected to be further improved.